This device relates to an improvement in the field of power hand tools, and more particularly to rotary tools which generate large amounts of dust and particulate debris.
Rotary grinders and similar rotary power tools are used extensively in industry. More specifically angle type grinders/sanders having grinding discs or pads, are used for grinding concrete, fiberglass, wood, steel, removing asbestos, and body filler in automobile shops. Such grinders/sanders are also used for making boats and similar products. In use these grinders create large quantities of dust that are both a fire hazard and a health hazard. Wood dust, for example, can be very explosive over a wide range of concentrations and is a known fire hazard. Hot metal grindings are particularly dangerous as fire starters. Both wood dust and metal filings as well as asbestos particles, fiberglass and body filler particles create known health hazards to users of the grinders and to others in the immediate environment. It is known that concrete dust, as typically generated in great quantities from grinding concrete, is a principal cause of pulmonary silicosis.
Grinder discs and pads often rotate in excess of 7,000 revolutions per minute (RPM). Grinding pads that use a sponge type backing material create a hazard where parts or particles from the backing material break off and are shot from the rotating disc tangently at a high rate of speed. It is often necessary to use a rotary grinder to grind into corners or against surfaces that have side edges, that can cause particles of the foam backing material to break off from the high speed rotating disc and hit the operator or other persons or equipment in the immediate area.
A dust shield described in U.S. Pat. No. 5,125,190 approached this problem and solved it to some extent. It has an upstanding attachment collar [reference character 16 of U.S. Pat. No. 5,125,190] which was diametered to fit onto the bearing housing [reference character 38 of U.S. Pat. No. 5,125,190] of a variety of different grinders. Different make grinders have different diameters for their respective bearing housing. Typical diameters of bearing housing range from one and one-half inch to three inches. A one-size attachment collar on the dust shield would not accommodate the different bearing housings. Consequently, several different models of the dust shield, each having different collar diameters, had to be manufactured for the various make grinders or requires an adapted. This, of course, increases manufacturing costs and adds to inventory of a supplier and end-user since most end-users have more than one grinder and more than one make.
Without the adapter, the retailer generally must carry up to 40 SKUs (stock keeping units) to cover all the grinders made. With the adapter, the retailer will need only 6 stocking units, one for each of the major disc diameters of 2, 3, 5, 6, 7 and 8 inches. Space in a retail store is very valuable. This adds value to the adapter because it can reduce the amount of space needed to provide a line of dust shields that can fit all grinders.
Additionally, the grinding surface of different brands of grinders with different grinding disks varies in distance from the bearing housing of the grinder where the dust shield is attached. The dust shield of U.S. Pat. No. 5,125,190 was not readily capable of a distance adjustment to bring the grinding surface down to where it can be of effective use or, in some cases, any use at all. The collar (reference character 16 of U.S. Pat. No. 5,125,190) had to be individually and carefully sanded down such that its lower edge (reference character 35 of U.S. Pat. No. 5,125,190) was accordingly raised thereby bringing the grinding surface out to point of use. Cutting the skirt, improper sanding, or improper measurements would in essence ruin the dust shield and be a waste of time and money.
My co-pending application and the new adaptive dust shield, in particular, solves the problems associated with various make of grinders as to different bearing housing diameters and different distance adjustments. The fitting ring and a modified dust shield of the adaptive dust shield will solve the onerous need to produce and inventory up to 40 dust shields to cover all the grinders commercially available and the need for the operator to modify the structure of the adaptive dust shield to accommodate different thicknesses of grinding disks and different bearing housing to disk surface dimensions. Additionally, it is simpler in construction, application, and use.
Additionally, the formulation for the manufacture of the adaptive dust shield is such that, if cutting the adaptive dust shield is necessary, it can easily be cut with ordinary household scissors without ruining the adaptive dust shield in its entirety. The formulation for the manufacture provides for greater flexibility, particularly where most critical, thereby eliminating much of the need to make distance adjustments of the fitting ring into and away from the bearing housing and into and away on the upstanding fingers.
The formulation also is such that it renders the adaptive dust shield of this present device more durable and virtually incapable of being damaged in extremely cold climates, even in temperatures as low as −20° Fahrenheit. Lastly, the fitting ring of this adaptive dust shield is flexible and with the cut-outs, can easily fit onto any diameter bearing housing from one and one-half inches to over three inches if necessary.
The foregoing has outlined some of the more pertinent objects of the adaptive dust shield. These objects should be construed to be merely illustrative of some of the more prominent features and applications of the adaptive dust shield. Many other beneficial results can be attained by applying the disclosed adaptive dust shield in a different manner or by modifying the adaptive dust shield within the scope of the disclosure. Accordingly, other objects and a fuller understanding of the adaptive dust shield may be had by referring to the summary of the adaptive dust shield and the detailed description of the preferred embodiment in addition to the scope of the adaptive dust shield defined by the claims taken in conjunction with the accompanying drawings.